|Weapons:||Armour-piercing heat gun|
|Color:||Silver, Dark Green|
|Character controlled by:||-Blackout-|
Yassen Gregorovich is a Vortixx, and one of the best assassins in the Matoran Universe. He was hired by Blackout in order to bring Ynot to Destral. He survived that mission, and remains at large. He is also the former owner of one of three armour-piercing heat guns in existence. Ravat assaulted him and stole it, while also removing one of his arms and an eye.
- Yassen Gregorovich is based on a villain in the Alex Rider book series.